Resumen

Background The efficacy of primary angioplasty is limited due to the fact that a considerable number of patients do not achieve adequate levels of myocardial tissue perfusion. The degree of reperfusion depends on multiple clinical, angiographic and therapeutic factors. Objectives To identify the independent factors associated with the absence of myocardial tissue reperfusion after primary angioplasty. Material and Methods A total of 140 patients included in the Protection of Distal Embolization in High-Risk Patients with Acute ST-Segment Elevation Myocardial Infarction Trial (PREMIAR) were analyzed. This study evaluated the use of filter distal protection device during angioplasty in patients with acute STsegment elevation myocardial infarction at high risk of thrombosis (only including baseline TIMI grade 0-2 flow). The primary end point of the study was the rate of complete ST-segment resolution at 60 minutes, defined as ≥ 70% recovery compared with baseline during continuous ST-segment monitoring. A model of logistic regression was developed to identify independent predictors. Results Complete resolution of ST-segment deviation 60 minutes after angioplasty was observed in 82 patients (63%), while 53 patients (37%) presented partial ST-segment resolution which was associated with rates of mortality, reinfarction and/or heart failure at 30 days of 8.5% and 18.9%, respectively (p=0.07). The variables associated with absence of adequate myocardial tissue reperfusion were anterior infarction (79% versus 33%; p=0.001), higher heart rate (81±20 versus 70±15; p=0.001) and history of current smoking (25% versus 51%; p=0.002), compared to optimal tissue reperfusion. In addition, there was a trend towards greater prevalence of diabetes (26% versus 16%; p=0.13), longer time interval from the onset of symptoms to angioplasty (minutes) (217±167 versus 182±134; p=0.19) and Killip class >1 (30% versus 17%; p=0.07), respectively. Multivariate analysis demonstrated that anterior myocardial infarction was associated with absence of complete reperfusion (OR 8.22, 95% CI 3.67-18.4; p<0.001), while the use of glycoprotein IIb/IIIa inhibitors (OR 4.21, 95% CI 1.34-13.22; p=0.014) and current smoking (OR 3.84, 95% CI 1.58-9.50; p=0.003) correlated with complete reperfusion. Conclusions A considerable proportion of patients undergoing primary angioplasty do not achieve adequate myocardial tissue reperfusion. This phenomenon is associated with adverse outcomes. Anterior myocardial infarction correlates with less degree of tissue reperfusion. Conversely, current smoking and the use of glycoprotein IIb/IIIa inhibitors are associated with better tissue reperfusion after primary angioplasty.